To begin the impact test of glass fiber reinforced polymer or GFRP composite laminates. Cut a set of 150 millimeter by 100 millimeter GFRP samples using a high precision cutting machine. Record the weight and size of each sample.
Then mark the positions of the samples using positioning nails in their centers that the impactor can contact for every test. Fix the sample onto the impact support fixture using four rubber tips. Power on the drop hammer testing machine to conduct the impact test using a drop weight impact tower.
After connecting it to the controller click home to do the beam reset and then click before test. Input the measurement thickness as 2.1 or 2.5 millimeters for WLVB or WL samples respectively. Set the additional mass to two kilograms and the impact energy to 10 joules.
Click start to initiate the experiment. Record the impact response data such as force, deflection, and energy history. Remove the sample and document its morphology after the impact.
Finally, calculate and compare the data of each sample. Great repeatability of the impact test was evident from the obtained force and absorbed energy curves of samples fabricated by WLVB and WL methods. The force time curve represented a typical non-piercing curve having a sine wave-like shape.
The absorbed energy value increased first with the laminate absorbing and converting the impactor's kinetic energy into its internal energy. And then the value decreased over time as the laminate released elastic energy to rebound the impactor. The specific absorbed energy of the WLVB sample was larger than that of the WL sample.
The WLVB laminates absorbed 19.48%more specific energy compared to the WL ones. Further, the higher impact energy absorption capacity of WLVB samples was confirmed by their relatively smaller damaged area.
